The ups and downs of doing online multiplayer as an indie

With the recent launches of local multiplayer games like TowerFall, Samurai Gunn and Sportsfriends, players are making their arguments for the inclusion of online multiplayer.

For developers, the issue of online multiplayer goes something like this: Sure, adding online multiplayer to your game is massively time-consuming, very costly, and not exactly the greatest fun you'll ever have -- but it can potentially bring in multitudes of extra players and sales, so it's always worth it, right?

Of course, we all know this isn't always the case, thanks to as plethora of examples were developers have put time and energy into including online multiplayer options, only to find that no-one bothers using them, and expensive servers remain dead and empty.

So when is the right time to add online multiplayer to your game, and how much effort is it going to take? Gamasutra talked to half a dozen developers who have integrated online multiplayer features in their games, to find out what the experience was like, and whether they'd do it again.

ibb & obb is a co-op platforming in which two players work together to tackle a variety of puzzles and obstacles. The game was released on PlayStation 3 last summer, and is about to hit Steam on May 26.

Richard Boeser from Sparpweed Games tells me that, "deciding whether or not to go for online multiplayer was one of the hardest decisions, and I could probably talk a full hour on that."

The original plan was not to include online multiplayer in the initial release, and perhaps add it in later if the game sold well. However, Sony warned the team that co-op games on PSN were rarely local multiplayer only, and that it would be wise to invest the time in online co-op.

"I will definitely stay away from it if the game mechanics require accurate player-player interaction."

"We weren't fully convinced as we figured that on console most players would playibb & obblocally," says Boeser, "and we also felt it was by far the best way to experience the game."

So Sparpweed put Sony's advice on the backburner and chugged on with their local-only approach. However, as development drew close to completion, Boeser and co. had a change of heart, and the decision was finally made to postpone the launch in order to add online multiplayer.

Eight months later, the online multiplayer for ibb & obb was finally ready, and the game could release.

"For ibb & obb it was quite difficult," Boeser admits, "mostly because the interaction between the two characters is crucial. The players can push each other and need to be able to accurately jump from each other's head. Also the way our system works is that your own character never has lag and the other character is updated as well as possible. This makes it a lot more complex than just having one host and a laggy client."

It was the real-time collisions and precise timing that caused the most trouble when implementing online multiplayer, he notes. For a turn-based game it's easy enough, but when you're talking split-second movements and reactions, the difficulty level goes way up.

Looking back, Boeser isn't so sure that adding online multiplayer to the PS3 game was that important, since the game turned out to be perfect for couch play. However, he's happy that they did add it as, for the upcoming PC version, he believes far more PC players are going to want to play it online.

But would he do it again? Not in the near future, at least. "I will definitely stay away from it if the game mechanics require accurate player-player interaction," he notes. "Also, local multiplayer seems to be on a rise and we see local-only games appearing on PS4 even."

"I would be very surprised if we ever build online multiplayer into Chalo Chalo," he adds of Sparpweed's next game.

But having said that, he does admit that there's "something magical" about being able to connect with other players around the world.

"Journey showed that you can use this in elegant new ways," he says. "I'm sure I'll explore that some day in some game."

His advice to other indies considering adding online multiplayer to their games: "If your game is most fun locally and if adding online isn't going to be a piece of cake, then don't do it."

"If your game is most fun locally and if adding online isn't going to be a piece of cake, then don't do it.

Another game with an interesting online multiplayer history is Chompy Chomp Chomp, an arcade co-op chomper from The Utopian World of Sandwiches. The game is currently available on Xbox 360 and PC, and is coming to Wii U this year.

Interestingly, the Xbox 360 version features online play, while the PC version is local-only -- according to developer James Woodrow, this was down to online multiplayer in the PC version being too difficult to implement and test.

"The real difficulty for us was the type of game we were making," he notes. "Chompy Chomp Chomp is twitch-based, all on one screen, frantic and fast. Lag is unavoidable and it can ruin this type of experience."

All games have these same online problems, he reasons, but certain genres can hide the issues to make them less apparent. In a first-person shooter, for example, each player has their own view of the world, so it's easy to correct a server-based issue from their line of sight.

"This was our biggest challenge," he adds. "We did our best to optimize and move as little data as possible over the network to minimise this issue. It was never going to be perfect."